How to down grade from iOS 26 to iOS 18

My app worked correctly using iOS 18. I tried to down grade back to iOS 18, but there are no signed ipsw file available. How can I down grade my iphone back to iOS 18?

For help with iOS software updates, please post in the Apple Support Community. The Apple Developer Forums are for questions about APIs and features intended specifically for developers.

How to down grade from iOS 26 to iOS 18
 
 
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